1. Field of the Invention
The invention relates to a process and device for labeling or printing of stackable flower pots.
2. Description of Related Art
A process and device for labeling of flower pots are known from practice, the flower pots being supplied individually to a labeling means. After labeling, the individual flower pots are stacked, packed into cartons, and shipped. This known process has the defect that the labeling speed is comparatively low. Furthermore, a process for printing of flower pots is known from practice; it is carried out in the same way as the labeling process, only that printing is performed instead of labeling. The printing speed is also comparatively slow in this process.
The object of the invention is therefore to provide a process and device for labeling or printing of stackable flower pots with which the labeling or printing can be performed quickly and easily.
The aforementioned object is achieved in accordance with the invention essentially by the process in which containers are continuously removed from a stack and are printed or labeled as they are removed without reversal of their direction of movement. The object is achieved by the device of the invention in that the containers are fed by a first generally horizontal conveyor into a stack within roughly vertical orientated magazine located next to the printing or labeling mechanism, and from which containers are separated briefly for printing or labeling and then re-stacked for transfer to receiving area. The advantage of the invention lies in the result that a more or less continuous stack of flower pots to be labeled or printed is supplied, the stack is interrupted briefly only for labeling or printing and is re-assembled after labeling or printing. The essentially identical alignment of the conveying direction and the stacking direction directly before and after labeling or printing means that the directions are essentially coaxial or essentially parallel to one another. The high labeling or printing speed with the process and the device in accordance with the invention, therefore, ultimately arises due to the prompt unstacking of a continuous stack for labeling or printing. It was ascertained in tests that with the invention that a labeling speed of up to ten applied labels per second can be achieved.
Incidentally, it should be pointed out that the invention is used preferably for flower pots. In any case, the invention can be carried out with the aforementioned principle of the brief unstacking of a continuous stack as claimed in the invention also for other types of stackable containers, for example, cream or yoghurt cups. The following details therefore also apply to all stackable containers accordingly.
Preferably, it is furthermore provided that the magazine has an elongated guide for the stack of flower pots to be labeled or printed and that the magazine has a feed conveyor belt for transfer of the flower pots to the guide. Basically, it is also possible to label or print the flower pots in a horizontal or oblique state of the flower pots. The essentially vertical arrangement of the flower pots in labeling or printing is especially advantageous since, in this case, after labeling or printing, the force of gravity can be used to supply the just labeled or printed flower pots to the stack of already labeled or printed flower pots. The just labeled or printed flower pot then drops essentially by itself into the stack of labeled or printed flower pots and is automatically stacked up again. Structurally, this is achieved by a guide in the area of the labeling or printing means having a roughly vertical alignment.
With respect to the high labeling or printing speed which is ensured by the process and the device as in accordance with the invention, it is a good idea for the flower pots to be supplied to the magazine in stack form. To do this, there are two basic possibilities, specifically, on the one hand, the flower pots are supplied such that the stacking direction and the conveyor direction are the same during supply via a feed conveyor belt. Ultimately, then, the magazine is supplied with a single, more or less endless stack which is refilled again and again manually or mechanically. The other possibility is that the conveyor direction, during supply via the feed conveyor belt, is offset by 90 degrees relative to the stack direction. In doing so, then individual stacks are always introduced into the magazine. Structurally, to implement the aforementioned alternative of feeding the stack of flower pots such that the stacking direction and the conveyor direction are the same, it is provided that the guide is tilted on its end facing the feed conveyor belt in the direction toward the feed conveyor belt. In the other alternative embodiment, on the feed conveyor belt there are receivers for positioning of the vertical stack of flower pots which are to be labeled or printed. The individual, smaller supplied stacks are then tipped by the feed conveyor belt into the stack which is located in the guide of the magazine.
Since flower pots and other stackable containers can have different sizes, it is especially advantageous if the unstacking means and the labeling or printing means can be adjusted in the x, y and/or z direction relative to one another. In this way, the device as in accordance with the invention can be matched to any conditions.
The at least partial unstacking of the flower pots for labeling or printing can take place via different structural means. In one alternative, the unstacking means has two arms which fit periodically into the stack. While one of these arms, on the one hand, is used for holding one flower pot to be labeled or printed, and on the other hand, for subsequent removal of the flower pot from the stack after labeling or printing, the other arm is used solely for holding the stack in the magazine over the flower pot to be labeled or printed. In another alternative version, there is a worm with a spiral pitch which becomes smaller in the direction away from the labeling or printing means and which becomes larger in the direction toward the labeling or printing means. This embodiment offers the additional advantage that, on the side opposite the labeling or printing means, before, during and after labeling or printing there is always guidance for the flower pots. Finally, the unstacking means also on opposite sides can have rotating means which are driven preferably roughly at a right angle to the labeling or printing direction and which cause at least partial unstacking of the flower pots in the area of the labeling or printing means. Otherwise, of course, there are also other basic possibilities for unstacking.
The flower pots can be printed in any known manner of printing. Preferably, ink is sprayed on the flower pot. The printing means therefore has no direct contact with the flower pot. Labeling can be done in different ways. On the one hand, it is fundamentally possible to roll on the labels. But preferably, the labels are applied pneumatically, i.e., blown onto the respective flower pot. This also enables a high labeling speed of the device and the process. Since it can happen that the labels do not adhere completely to the respective flower pots, to ensure a smooth process, it is provided that the labels are pressed on after application in an additional pressing step before the just labeled flower pot is supplied to the stack of already labeled flower pots. Structurally, this is done by there being a pressing means for pressing the label which has been applied to the flower pot directly adjacent to the labeling means, and in one simple embodiment, the pressing means have brush filaments or another elastic material.
Especially in conjunction with the aforementioned pressing means, but essentially also when there are none of these pressing means, it is a good idea when, immediately after labeling or printing, a pressure blast directed into the flower pot is produced in order to accelerate the re-stacking or downward motion of the just labeled or printed flower pot. Structurally, for this purpose, there is a pneumatic pressure blast means for producing the pressure blasts which are directed in the flower pot immediately after labeling or printing.
To ensure the continuous removal of the labeled or printed flower pots, it is provided during removal that the stack of labeled or printed flower pots is supplied to a discharge conveyor belt of the removal means, the conveyor and stacking direction of the stacked flower pots on the discharge conveyor belt being the same. Structurally, in the discharge conveyor means, there is a guide following the unstacking means and the aforementioned discharge conveyor belt which follows the guide in order to supply the stack of labeling or printed flower pots to the discharge conveyor belt.
Since the labeled or printed flower pots are generally sold packed in cartons in smaller stacks, within the framework of the process in accordance with the invention, it is additionally provided that the continuous stack of labeled or printed flower pots on the discharge conveyor belt are separated into smaller stacks with a stipulated number of the labeled or printed flower pots, the smaller stacks being tipped off the discharge conveyor belt and preferably roll into a ready carton. Structurally, for this purpose, there is a separation means, especially in the area of the belt end of the discharge conveyor belt, for producing smaller stacks with a predetermined number of flower pots, and following the separation device, there can be a tipping means. This can have a slider which can be moved transversely to the conveyor direction and which tips the individual small stacks over a corresponding ramp.
The entire labeling or printing process according to the invention is preferably controlled by a corresponding control means. The speeds of the feed conveyor belt, the discharge conveyor belt, unstacking, labeling or printing and/or separation and/or tipping are adjustable and are matched to one another especially such that the labeling or printing process is continuous.
The process and the device in accordance with the invention are especially suited when small labels or print areas are to be applied to the flower pots. In this case, brief unstacking is enough for labeling or printing. After the labeling or printing process, the respective flower pot is stacked again, the conveyor direction and the stacking direction being coaxial immediately before and immediately after labeling or printing. When larger labels or print areas are to be applied to the flower pot, it is a good idea to remove the respective flower pot entirely from the respective stack. In this case, the flower pot is then supplied to a conveyor means which moves roughly transversely to the stacking direction. On the conveyor means which can be, for example, a turntable or an elongated guide in the form of a conveyor belt, the flower pot is then freely accessible so that the label or printing can be applied. For very long labels or print areas, the flower pot can be turned around its middle axis in the area of the conveyor means up to 360xc2x0. Rotation of the respective flower pot can be accomplished via two guide rails which move relative to one another and which are located on opposite sides and which are in contact with the flower pot. The relative motion of the guide rails and the flower pot which is located in between causes rotation of the flower pot. In doing so, one of the guide rails can even be made as a label dispenser or printing head so that, during rotation of the flower pot, the label or the printing can be applied. After labeling or printing, the respective flower pot is again supplied to the stack of already labeled or printed flower pots so that, ultimately, a continuous stack of flower pots is removed.
Other features derive from the following description of embodiments using the drawings and the drawings themselves.